Patterning of Silicide Layers by Local Oxidation

Abstract

AbstractA novel method for patterning of silicide layers based on local oxidation is presented. We investigated unifom and local oxidation of epitaxial CoSi2 layers on Si(100). During thermal oxidation of CoSi2 a SiO2 surface layer forms and the silicide layer moves deeper into the substrate. Single crystalline CoSi2 layers on Si(100) remain single crystalline even if they are shifted into the substrate several hundred nm. Local oxidation of such a silicide layer allows lateral patterning of the silicide. The oxidized regions of the silicide layer are pushed inwards and separate from the surface layer at a critical oxidation time. This allows the formation of buried patterned silicides or metallized mesa structures. The technique seems to be also applicable for polycrystalline silicides.